Improvement in joiners clamps



UNITED STATE-s PATENT OFFICE GUSTAV A. NAUMANN, OF S'I. LOUIS, MISSOURI.

IMPROVEMENT IN JOINERS CLAMPS.-

Specication forming part of Letters Patent No. l 69,027. dated October19, 1875; application led September 6, 1875.

To all whom it may concern:`

Be it known that I, GUsTAv ADOLPH NAU- MANN, ot' St. Louis, Missouri,have invented an Improved J oiners Olamp, of which the following is aspecitication:

The ordinary clamp-screw consists of jaws or holders operated by woodenhand-screws reversely positioned, so that, to adjust and use thejaws orclamps Lfor holding work, it is necessary to turn both screws inopposite directions. This to do, in large clamp-screws, more especially,is very ditlicult; also, said screws project in opposite directions,rendering the device inconvenient, cumbersome, and and difficult foroperating, turning, or handling; nor can the device holding` the work belaid down or positioned in accordance with the position best suited tothe nature of the Work. All this to avoid isthe object of myimprovement; and it consists in the novel construction and combinationof its parts in manner now to be more fully described.

Of the drawing, Figure l is a sectional elevation. Fig. 2 is aplansection ot' the Inovable jaw on line x x.

A is the Xed jaw, constructed as ordinary. B is the movable jaw. B1B2are the handscrews. The hand-screws I have both positioned alike, bothrunning through the upper jaw B, and both secured in the txed jaw A, asshown in Fig. l. To dispense with the constant screwing together andapart ot' the jaws, I make the movable jaw B capable ot' being broughttoward or away from the jaw A by sliding on the screws. This Iaccomplish as follows: The jaw B I make hollow almost its entire length.(See Figs. l and 2.) In its hollow is a slide, O, which is made otf theconstructive shape shown in Fig. 2, having slots cc', for the doublepurpose of allowing the screws B1 B2 to pass through, as well as tolighten the weight of the slide. The back sides of the slots cc havethreads cut in them, (see Fig. 1,) to engage the threads of thehandlscrews, and are held in engagement with the latter by a spring, D,inserted behind the slide. (See figures.) lSimilarly I provide theopposite sides of the slots d d ot' the jaw B with screw-threads,indicated in Fig. l.

to narrow, or vice versa, the end of the slide' projecting out at theback of' the jaw B is pressed in by the operator, which compresses thespring, and disengages the threaded sides oi the slide from thehand-screws, and said screws from the threads in the upperjaw, and thussaid jaw is capa-ble of being adjusted as the nature of the workrequires. the operators hold on the slide is released, the springrestores said slide in original engagement with the hand-screws.

lhe screws B1 B2 I prefer making of metal, having the threads thereofrunning reversely, (see Fig. 1,) so that the engagement described withthe threads in thejaw B, as well as slide O, can be had. Also, the slideis of metal. The device is, therefore, durable, cheap, and

its advantages over ordinary clamps ot' this character apparent.

What I claim is- The combination of' the movablejaw B, carrying theslide O, having slots c c', the spring D, the hand-screws 151132, havingbearing-surface of threads reversed, all said parts being constructedand arranged to operate With relation to each other and a fixed jaw, A,substantially as is herein shown and described, and for the purpose setforth.

In testimony of said invention I have hereunto set my hand.

GUSTAV ADOLPH NAUMANN.

Witnesses WiLLrAM: W. HERTHEL, CEAS. F. MErsNER.

As soon asv

